1. Field of the Invention
The present invention refers to a universal mowing head for flexible cutter, aimed in particular to be used as cutting head for bush-cutters.
2. Background Art
As known, the bush-cutter is a tool used for cutting bushes, shrubs and grass in places not accessible with other machines. It is carried on straps or on the shoulders by an operator and is equipped with an engine of the electric or combustion type that, through a transmission shaft placed inside a rod, actuates, by rotating it, a rigid toothed disk or a mowing head that usually supports from two to four flexible cutters, made as nylon wires, thin metal cables or chains.
In the particular case of mowing heads, flexible cutters made as nylon wires are usually wound around a spring-loaded coil contained inside the head itself, from which they can be unwound and delivered outside, either manually by the operator for the length that is deemed appropriate for performing the work, or automatically by exploiting the centrifugal force that is generated upon rotating the mowing head during its use.
Such heads however are often technically and mechanically very complex and therefore, in addition to being relatively costly, they have a common disadvantage pertaining to their reliability: such heads, in fact, suffer the inconvenience that they get often jammed when the operator tries to remove new wires from the coil, for example if the one already inside it is damaged or broken. When this occurs, the operator must stop his moving work, disassemble the mowing head, unlock the coil and re-assemble the head in order to be able to restart working. Moreover, not rarely such inconvenience occurs rather frequently during the mowing work. It is clear therefore that these continuous interruptions bring about unpleasant losses of time, in addition to an unavoidable frustration for the operator.
In simpler and more inexpensive versions of the mowing heads, above all when the cutter is of the chain type, flexible cutters are simply fastened on their external surface, for example through screws or bolts. Also in this case, the replacement of a broken or damaged cutter requires a not neglectable time and often the use of tools, at the same time resulting as extremely frustrating for the operator.
Moreover, in case of work which requires the following use of different types of cutters, the operator must have available different heads for each type of cutter, and must stop in order to replace them at suitable times. In fact, the art does not provide for a mowing head that can, depending on specific working needs, allow an operator to indifferently use any type of flexible cutter, both made as a nylon wire, metallic or textile cable, chain or other, always with the same mowing head, after a simple and quick intervention activity on the head in order to install thereon the desired cutter. Also in this case, the mowing activity, in addition to be obviously expensive since it necessarily provides for the purchase and use of different heads, performed as such for every type of cutter, often requires long stops in order to proceed with their replacement.